I have a 2015 Silverado with the 4.3L ecotec. I just took it in for a couple of recalls 2 weeks ago. 1 recall was a seatbelt issue and the other was an issue with the transmission potentially jumping out of 4 wheel drive in cold weather. To fix this problem the dealership had to "reprogram the computer". Previous to this recall I was getting 23-26 MPG. Now I am getting 19-21 MPG. Anyone else experiencing this after the recall?